Jack Brennan

John Vincent "Jack" Brennan (16 August 1937-) was a US Marine Corps colonel during the Vietnam War who served as a political aide to President Richard Nixon, later serving as his post-resignation chief-of-staff.

Biography
John Vincent Brennan was born in Fall River, Massachusetts on 16 August 1937, and he graduated from Providence College in 1959. Brennan served in the US Marine Corps during the Vietnam War, earning a Bronze Star and Purple Heart Medal at the Battle of Khe Sanh in 1968. In 1969, he became a Marine Corps aide to President Richard Nixon, and he became a colonel and one of Nixon's most trusted aides. After Nixon's resignation, Brennan left the Marines to become his post-resignation chief-of-staff, managing the small staff, appointments, mail and budgets, and investigations into the Watergate scandal. Brennan warned David Frost not to change any of the footage from his 1977 interview with Nixon, and he ensured that Frost did not get any facts wrong.